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<html lang="en">
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    <meta charset="UTF-8" />
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    <title>Document</title>
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  <body>
    <script>
      // forEach 迭代(遍历) 数组
      var arr = [1, 2, 3]
      var sum = 0
      arr.forEach(function (value, index, array) {
        console.log("每个数组元素" + value)
        console.log("每个数组元素的索引号" + index)
        console.log("数组本身" + array)
        sum += value
      })
      console.log(sum)
    </script>
  </body>
</html>
